Where is the "go!" button on the render tab in 2.8?
First (1) Setup your size and output
Second (2) check your layers ready to be rendered.

Then go to the Render menu and select Render (F12). This is the default "GO" button on Blender 2.8. I know you´re asking for the big buttons on 2.79, they´re gone.



A lot of users on the Blender community are asking for those buttons to be back, you're not the only one. This was a recent change.